Backward centrifugal impeller and centrifugal fan

Abstract

The backward centrifugal impeller comprises an annular rear wheel disc (11), a front wheel disc (12) and a plurality of fan blades (13), a mounting hole (110) used for mounting a motor is formed in the center of the rear wheel disc (11), an air inlet (120) is formed in the center of the front wheel disc (12), the fan blades (13) are mounted between the rear wheel disc (11) and the front wheel disc (12), and an air channel (130) is formed between every two adjacent fan blades (13). An air outlet (131) is formed in the outer edge of the air channel (130), a notch (133) is formed in the position, at the air outlet (131), of the bottom end of the edge (132) of the fan blade (13), the edge of the rear wheel disc (11) is flush with the bottom edge (1331) of the notch (133), and the front wheel disc (12) is flush with the edge (132) of the fan blade (13). The gaps are added, so that eddy current and resistance generated in the rotating process of the fan blades can be reduced, power is reduced, and temperature rise of the motor is reduced.

Description

Technical Field

[0001] This utility model relates to a backward centrifugal impeller and a centrifugal fan. Background Technology

[0002] The existing backward centrifugal impeller structure can be found in patent number 201920417311.6, entitled "A Utility Model Patent for a Backward Centrifugal Fan with a Flow Guiding Device," for details. Figure 1 As shown, the outer diameter of the rear wheel 2a is the same as that of the front wheel 1a. At the air outlet, the top and bottom of the edge of the fan blade 3a are flush with the edges of the rear wheel 2a and the front wheel 1a, respectively.

[0003] A backward centrifugal fan mainly consists of an impeller, guide vanes, and a motor. Using an impeller with this structure, an improperly designed straight blade in a backward centrifugal fan can lead to numerous eddies in the airflow field, causing eddy current losses, increased resistance, decreased ventilation performance, increased motor temperature rise, and reduced motor lifespan. Motor temperature rise refers to the increase in temperature of various parts of the motor due to heat generated during operation. The centrifugal fan blades affect heat dissipation, thus influencing the motor's temperature rise. Summary of the Invention

[0004] The purpose of this invention is to provide a backward centrifugal impeller and a centrifugal fan, solving the technical problem in the prior art where the outer diameters of the rear and front impellers are the same, and the top and bottom edges of the fan blades at the air outlet are flush with the edges of the rear and front impellers respectively. This results in numerous eddies in the airflow field, causing eddy current losses, increased resistance, decreased ventilation performance, increased motor temperature rise, and reduced motor lifespan.

[0005] The technical solution of this utility model is implemented as follows:

[0006] A backward centrifugal impeller includes an annular rear impeller, a front impeller, and several fan blades. The rear impeller has a mounting hole at its center for mounting a motor, and the front impeller has an air inlet at its center. The several fan blades are installed between the rear impeller and the front impeller, and an air duct is formed between two adjacent fan blades. An air outlet is formed at the outer edge of the air duct. The impeller is characterized by having a notch at the air outlet and at the bottom edge of the fan blade. The edge of the rear impeller is flush with the bottom edge of the notch, and the front impeller is flush with the edge of the fan blade.

[0007] The top of the bottom edge of the aforementioned notch is connected to the bottom edge of the fan blade by an inclined connecting edge.

[0008] The ratio of the height H1 of the aforementioned notch to the edge height H2 of the fan blade is in the range of 1 / 5 to 1 / 3.

[0009] The diameter of the front wheel is larger than the diameter of the rear wheel.

[0010] The outer diameter of the front wheel disc is D1, and the outer diameter of the rear wheel disc is D2, with the ratio of D2 to D1 ranging from 0.8 to 0.98.

[0011] A centrifugal fan includes a motor and a centrifugal impeller, characterized in that: the centrifugal impeller is a type of backward centrifugal impeller as described above, and the motor is installed in the mounting hole of the rear impeller disc.

[0012] Compared with the prior art, this utility model has the following advantages:

[0013] 1. This utility model has a notch at the air outlet and the bottom edge of the fan blade. The edge of the rear wheel is flush with the bottom edge of the notch, and the front wheel is flush with the edge of the fan blade. The addition of the "notch" helps to reduce the eddies and resistance generated by the fan blade during rotation, reduce power, and thus reduce the temperature rise of the motor.

[0014] 2. The notch design reduces the amount of raw materials used in the impeller, lowers costs, and improves production efficiency.

[0015] 3. Other advantages of this utility model are described in detail in the embodiment section of the specification. Attached Figure Description

[0016] Figure 1 This is a three-dimensional view of a backward centrifugal impeller in the prior art;

[0017] Figure 2 This is a perspective view of the first angle of the backward centrifugal impeller provided by this utility model;

[0018] Figure 3 A second perspective view of the backward centrifugal impeller is provided for this utility model;

[0019] Figure 4 This utility model provides a third-angle elevation view of a backward centrifugal impeller;

[0020] Figure 5 yes Figure 3 A magnified view of part D;

[0021] Figure 6 A top view of the backward centrifugal impeller is provided for this utility model;

[0022] Figure 7 yes Figure 6 AA sectional view. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] Example 1:

[0025] like Figures 2 to 7 As shown, this embodiment provides a backward centrifugal impeller, including an annular rear impeller 11, a front impeller 12, and a plurality of fan blades 13. The rear impeller 11 has a mounting hole 110 for mounting a motor at its center, and the front impeller 12 has an air inlet 120 at its center. The plurality of fan blades 13 are installed between the rear impeller 11 and the front impeller 12, and an air duct 130 is formed between two adjacent fan blades 13. An air outlet 131 is formed at the outer edge of the air duct 130. The characteristic feature is that a notch 133 is cut at the air outlet 131 and at the bottom end of the edge 132 of the fan blade 13. The edge of the rear impeller 11 is flush with the bottom edge 1331 of the notch 133, and the front impeller 12 is flush with the edge 132 of the fan blade 13.

[0026] The backward centrifugal impeller of this invention has a notch 133 cut at the air outlet 131 and the bottom edge 132 of the fan blade 13. The edge of the rear impeller 11 is flush with the bottom edge of the notch 133, and the front impeller 12 is flush with the edge 132 of the fan blade 13. The addition of the notch helps to reduce the eddies and resistance generated by the fan blade during rotation, thereby reducing power consumption and reducing motor temperature rise. The notch 133 reduces the amount of raw materials used in the impeller, lowers costs, and improves production efficiency.

[0027] The top of the bottom edge 1331 of the aforementioned notch 133 is connected to the bottom of the edge 132 of the blade 13 by an inclined connecting edge 134, further reducing the vortex and resistance generated by the blade during rotation.

[0028] The ratio of the height H1 of the notch 133 to the height H2 of the edge 132 of the blade 13 is in the range of 1 / 5 to 1 / 3. The proportion is properly matched, which reduces the eddies and resistance generated by the blade during rotation and reduces power.

[0029] The diameter of the front impeller 12 is larger than that of the rear impeller 11. The outer diameter of the front impeller 12 is D1, and the outer diameter of the rear impeller 11 is D2. The ratio of D2 to D1 is in the range of 0.8-0.98, which reduces the raw materials of the impeller and lowers the cost.

[0030] Example 2:

[0031] A centrifugal fan includes a motor and a centrifugal impeller, characterized in that: the centrifugal impeller adopts a backward centrifugal impeller as described in Embodiment 1, and the motor is installed in the mounting hole 110 of the rear impeller 11.

[0032] The backward centrifugal impeller of this invention has a notch 133 cut at the air outlet 131 and the bottom edge 132 of the fan blade 13. The edge of the rear impeller 11 is flush with the bottom edge of the notch 133, and the front impeller 12 is flush with the edge 132 of the fan blade 13. The addition of the notch helps to reduce the eddies and resistance generated by the fan blade during rotation, thereby reducing power consumption and reducing motor temperature rise. The notch 133 reduces the amount of raw materials used in the impeller, lowers costs, and improves production efficiency.

[0033] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited thereto. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model are equivalent substitutions and are included within the protection scope of the present utility model.

Claims

1. A backward centrifugal impeller, comprising an annular rear impeller (11), a front impeller (12), and a plurality of fan blades (13), wherein the rear impeller (11) has a mounting hole (110) for mounting a motor at its center, the front impeller (12) has an air inlet (120) at its center, the plurality of fan blades (13) are mounted between the rear impeller (11) and the front impeller (12), an air duct (130) is formed between two adjacent fan blades (13), and an air outlet (131) is formed at the outer edge of the air duct (130), characterized in that: At the air outlet (131), there is a notch (133) at the bottom of the edge (132) of the fan blade (13). The edge of the rear wheel (11) is flush with the bottom edge (1331) of the notch (133), and the front wheel (12) is flush with the edge (132) of the fan blade (13).

2. A backward centrifugal impeller according to claim 1, characterized in that: The top of the bottom edge (1331) of the notch (133) is connected to the bottom of the edge (132) of the blade (13) by an inclined connecting edge (134).

3. A backward centrifugal impeller according to claim 1 or 2, characterized in that: The ratio of the height H1 of the notch (133) to the height H2 of the edge (132) of the blade (13) is in the range of 1 / 5 to 1 / 3.

4. A backward centrifugal impeller according to claim 3, characterized in that: The diameter of the front wheel (12) is larger than the diameter of the rear wheel (11).

5. A backward centrifugal impeller according to claim 4, characterized in that: The outer diameter of the front wheel (12) is D1, and the outer diameter of the rear wheel (11) is D2, with D2 / D1 ranging from 0.8 to 0.

98.

6. A centrifugal fan, comprising a motor and a centrifugal impeller, characterized in that: The centrifugal impeller is a backward centrifugal impeller as described in any one of claims 1 to 5, and the motor is installed in the mounting hole (110) of the rear impeller (11).

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